Advances in Geosciences www.adv-geosci.net 1680-7340 1680-7359 26 11th EGU Plinius Conference on Mediterranean Storms (2009) 2010 10.5194/adgeo-26-65-2010 http://www.adv-geosci.net/26/65/2010/ http://www.adv-geosci.net/26/65/2010/adgeo-26-65-2010.html http://www.adv-geosci.net/26/65/2010/adgeo-26-65-2010.pdf 65 69 2010-07-09 Spatial variability and trends of the rain intensity over Greece H. D. Kambezidis I. K. Larissi P. T. Nastos nastos@geol.uoa.gr A. G. Paliatsos Atmospheric Research Team, Institute of Environmental Research and Sustainable Development, National Observatory of Athens, P.O. Box 20048, 118 10 Athens, Greece Laboratory of Environmental Technology, Technological Education Institute of Piraeus, 122 44 Athens, Greece Laboratory of Climatology and Atmospheric Environment, Faculty of Geology and Geoenvironment, University of Athens, Panepistimiopolis, 157 84 Athens, Greece General Department of Mathematics, Technological Education Institute of Piraeus, 122 44 Athens, Greece In this study, the spatial and temporal variability of the mean annual rain intensity in Greece are examined during a 41-year period (1962–2002). The meteorological datasets concern monthly rain amounts (mm) and the respective monthly durations (h) recorded at thirty two meteorological stations of the Hellenic National Meteorological Service, which are uniformly distributed on Greek territory, in order to calculate the mean monthly rain intensity. All the rain time series used in the analysis were tested by the application of the short-cut Bartlett test of homogeneity. The spatial distribution of the mean annual rain intensity is studied using the Kriging interpolation method, while the temporal variability, concerning the mean annual rain intensity trends along with their significance (Mann-Kendall test), is analysed. <br><br> The findings of the analysis show that statistically significant negative trends (95% confidence level) appear mainly in the west sub-regions of Greece, while statistically significant positive trends (95% confidence level) appear in the wider area of Athens and the complex of Cyclades Islands. Further analysis concerning the seasonal rain intensity is needed, because there are different seasonal patterns, taking into account that, convective rain in Greece occurs mainly within the summer season. 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